Global-Warming Skeptics: Might Warming Be 'Normal'?

Knickerbocker, Brad, The Christian Science Monitor

In a small college town like Corvallis, Ore., it's not unusual
that George Taylor would ride a bike to his job on the Oregon State
University campus. He commutes this way for the exercise, he says,
but also because it's good for the planet.

Mr. Taylor manages the Oregon Climate Service, and much of his
work has to do with global warming. "I'm certainly in favor of doing
prudent things to reduce the human impact," he says.

But unlike most climate scientists, he does not believe that
anthropogenic (human-caused) greenhouse gases - mainly from coal-
fired power plants and motor vehicles spewing carbon dioxide - are
the main culprits. In fact, he says, "It's my belief that in the
last 100 years or so natural variations have played a bigger role."

Among the forces of nature he cites are changes in solar
radiation, "very significant influences" of the tropical Pacific (El
Nino and La Nina events in decades-long cycles), as well as changes
in Earth's tilt and orbit over cycles lasting thousands of years.

Above all, says Mr. Taylor, who is past president of the American
Association of State Climatologists, "The climate system is very,
very complex, and the more we learn, the more we see that we really
don't understand it."

Taylor may be in the minority among climate experts, but he is
not alone.

Other planets in our solar system have expanding and contracting
ice caps, too, other skeptics point out, and those worlds have no
people as far as we know - certainly no gas-guzzling muscle cars and
trucks. Antarctica and Greenland at times have been warm and green
before humankind inA-A-vented machines, indicating to these skeptics
that this is just a natural cycle.

In Phoenix, where it's been very hot indeed this summer, Warren
Meyer has written "A Skeptical Layman's Guide to Anthropogenic
Global Warming." He is not a professionally trained climate
scientist, but he studied physics and engineering at Princeton
University, then earned an MBA at Harvard University before entering
the business world.

Like Taylor, Mr. Meyer cites other possible factors - ocean
oscillations and currents, sunspot cycles, and recovery from the
"Little Ice Age" (which ran for roughly three to four centuries, up
to the mid-19th century) - to argue that "we are a long way from
attributing all or much of current warming to man-made carbon
dioxide."

He says he's carefully studied the official reports and
assertions about global warming and come to the conclusion that
"it's a funny sort of anthropomorphic hubris to say that we know
what 'normal' is or even know what the cycles are.

"Look, there's a lot going on here that we've observed for a very
short time," Mr. Meyer says. "We have all these complicated cycles
happening, and many of them last for thousands or millions of years.
And we've observed them carefully for - what? - 30 years?"

Is climate 'feedback' positive or not?

Meyer's engineering background is in feedback and control theory,
so he especially takes issue with the belief among many climate
scientists (as well as activists such as former Vice President Al
Gore) that what had been a long-term, stable climate system is now
dominated by "positive feedback ." Positive feedback means that as
temperatures rise in extraordinary fashion there will be a tendency
for global warming to speed up. One example is when light-colored
sea ice melts to reveal darker ocean water, which in turn absorbs
more heat, which melts more ice.

Meyer contends that in physics (and in nature) the tendency is
just the opposite: a "negative feedback" will occur as CO2 levels
rise - in other words, cooling mechanisms will set in. In the case
of carbon dioxide and global temperature, "future CO2 has less
impact on temperature than past CO2," he says.

One bit of recent research may give some weight to Meyer's
argument.

Researchers at the University of Alabama's Earth System Science
Center in Huntsville studied heat-trapping tropical clouds thought
to result from global warming. …

The rest of this article is only available to active members of Questia

Print this page

While we understand printed pages are helpful to our users, this limitation is necessary
to help protect our publishers' copyrighted material and prevent its unlawful distribution.
We are sorry for any inconvenience.